Striker only synchronizes group membership with the backing LDAP directory when a user authenticates with the application. Two of the goals (join tool labs and become a tool maintainer) are evaluated based on group membership information. This means that a user must logout and log back into the application to complete these goals. This is not clear in the instructions.
It should be possible to refresh group membership information without logging out and the goals that are based on these group checks should provide an easy link to recheck the state.